Sean “Diddy” Combs has said he’s sorry after leaked surveillance footage showed the music mogul assaulting his then-girlfriend Cassie Ventura at a hotel in 2016, but people aren’t buying the apology, RadarOnline.com can report. “OMG. You swore you did nothing wrong. You gaslighted her and all of us, and ONLY now that the video came out, you’re sorry. Bro, go away,” one user commented on the rapper’s Instagram post. “And the award for the best liar goes to you,” another commenter added. “This isn’t even genuine.” Diddy spoke directly to the camera in the apology video posted to Instagram on Sun…